1. Field of the Invention
The present invention relates to an electrical connector, and particularly to an electrical connector having contact terminal made from wire so as to provide excellent wiping capability against pads of an electronic package.
2. Description of the Prior Art
Electrical connectors are widely used in electrically connecting electronic packages such as Land Grid Array (LGA) Central Processing Units (CPUs) with circuit substrates such as printed circuit boards (PCBs). Patented examples of such electrical connectors are disclosed in U.S. Pat. No. 4,553,192 issued to IBM on Aug. 25, 1983 and U.S. Pat. No. 6,296,495 issued to Hon Hai on Mar. 23, 2000.
Referring to FIG. 1, a conventional electrical connector connecting a CPU 51 with a PCB 61 is illustrated. The connector comprises an insulative housing 81 and a multiplicity of terminals 91 received in the housing 81. The housing 81 defines a multiplicity of passageways 810 therethrough, for receiving a corresponding terminals 91 therein.
Each terminal 91 comprises a retaining body 911 engagingly received in a corresponding passageway 810, a soldering portion 912 extending perpendicularly from a bottom end of the retaining body 911, and a cantilevered arm 913 extending slantingly upwardly from a top end of the retaining body 911 and formed with a curved contacting portion 9131 at the free end thereof. The soldering portion 912 electrically connects with the pad 612 of the PCB 61 via a solder ball 71, and the cantilevered arm 913 substantially protrudes beyond a top surface of the housing 81 with the contacting portion 9131 compressed by pads 512 of a CPU 51 for electrically connecting with the CPU 51, the connector thus electrically connects the CPU 51 with the PCB 61.
When the contacting portion 9131 of the terminal 91 engages with the pad 512, the cantilevered arm 913 rotates about a junction of the cantilevered arm 913 and the retaining body 911. The rotation comprises the component horizontal displacement and the component vertical displacement. Therefore, the effect of the horizontal displacement makes the cantilevered arm 913 wipes the pad 512 relative to the CPU 51 a certain distance during the downward movement of the CPU 51. The relatively long wiping length of the terminals 91 results in poor connection between the contacting portion 9131 and the pad 512.
In view of the above, a new electrical connector that overcomes the above-mentioned disadvantages is desired.